Jean Vincelette

Evidence for a correlation between antibody-dependent cellular cytotoxicity-mediating anti-HIV-1 antibodies and prognostic predictors of HIV infection

Using our gp120/41-expressing, NK cell activity-resistant CEM.NKR cell clones as targets in HIV-1-specific antibody-dependent cellular cytotoxicity (ADCC) assays, we demonstrate here that the serum titers of anti-HIV-1 ADCC antibodies bear a significant (P < 0.05) positive correlation with the peripheral blood CD4+ T cell counts and a negative one with the number of copies of HIV-1 RNA in the plasma of HIV-infected individuals. These findings underscore the importance of these antibodies as a protective immune parameter in these infections.

Lack of Evidence of Sexual Transmission of Hepatitis C Virus in a Prospective Cohort Study of Men Who Have Sex With Men

OBJECTIVES We studied the prevalence and incidence of hepatitis C virus (HCV) infection in the ongoing Omega Cohort Study of men who have sex with men (MSM). METHODS From January to September 2001, consenting men (n = 1085) attending a follow-up visit to the ongoing Omega Cohort Study were tested for HCV. If the test results were positive for HCV, we compared them with test results from previous serum samples collected from the time of entry into the original cohort study to determine the time of infection. RESULTS HCV prevalence at entry was 2.9% and was strongly associated with injection drug use (32.9% vs 0.3%, P<.0001). Only 1 seroconversion was identified in 2653 person-years of follow-up (incidence rate = 0.038 per 100 person-years). The seroconverter was an active injection drug user who reported needle sharing. CONCLUSIONS Sexual transmission of HCV among MSM appears to be rare.

Thiamine deficiency and wernicke's encephalopathy in AIDS

Several neuropathological reports in the last 5 years have described brain lesions characteristic of Wernickes Encephalopathy in patients with AIDS. Using the erythrocyte transketolase activation assay, we now report biochemical evidence of thiamine deficiency in 9/39 (23%) of patients with AIDS or AIDS-related complex. In no cases was there history of alcohol abuse nor were there clinical signs of Wernickes Encephalopathy. Thiamine deficiency in these patients most likely results from the cachexia and catabolic state characteristic of AIDS. In view of (i) the confirmed neuropathological evidence of Wernickes Encephalopathy in AIDS patients, (ii) the significant thiamine deficiency in these patients and (iii) the difficulties of clinical diagnosis of Wernickes Encephalopathy, it is recommended that dietary thiamine supplementation be initiated in all newly diagnosed cases of AIDS or AIDS-related complex.

Trends in Human Immunodeficiency Virus Incidence and Risk Behavior Among Injection Drug Users in Montreal, Canada: A 16-Year Longitudinal Study

The authors sought to investigate trends in the incidence of human immunodeficiency virus (HIV) infection, evaluate changes in risk behavior, and assess associations between syringe access programs and HIV seroconversion among injection drug users (IDUs) in Montreal, Canada, who were recruited and followed for a prospective cohort study between 1992 and 2008. Methods included Kaplan-Meier survival analysis and time-varying Cox regression models. Of 2,137 HIV-seronegative IDUs at enrollment, 148 became HIV-positive within 4 years (incidence: 3.3 cases/100 person-years; 95% confidence interval: 2.8, 3.9). An annual HIV incidence decline of 0.06 cases/100 person-years prior to 2000 was followed by a more rapid annual decline of 0.24 cases/100 person-years during and after 2000. Behavioral trends included increasing cocaine and heroin use and decreasing proportions of IDUs reporting any syringe-sharing or sharing a syringe with an HIV-positive person. In multivariate analyses, HIV seroconversion was associated with male gender, unstable housing, intravenous cocaine use, and sharing syringes or having sex with an HIV-positive partner. Always acquiring syringes from safe sources conferred a reduced risk of HIV acquisition among participants recruited after 2004, but this association was not statistically significant for participants recruited earlier. In conclusion, HIV incidence has declined in this cohort, with an acceleration of the reduction in HIV transmission after 2000.

Association of hepatitis B virus infection with other sexually transmitted infections in homosexual men

OBJECTIVES This study determined the prevalence and factors associated with hepatitis B virus (HBV) infection among men who have sex with men. METHODS At the baseline visit of an HIV study among men who have sex with men, we asked about HBV vaccination status and tested for HBV markers. RESULTS Of 625 subjects, 48% had received at least 1 dose of HBV vaccine. Of 328 unvaccinated men, 41% had 1 or more HBV markers. HBV prevalence increased markedly with age and was associated with many sexual and drug-related behaviors. In a multivariate model, 7 variables were independently associated with HBV infection: ulcerative sexually transmitted diseases (odds ratio [OR] = 10.1; 95% confidence interval [CI] = 2.6, 54); injection drug use (OR = 5.2; 95% CI = 1.2, 26); gonorrhea or chlamydia (OR = 4.0; 95% CI = 1.9, 8.9); sexual partner with HIV/AIDS (OR = 3.6; 95% CI = 1.8, 7.1); 50 or more casual partners (OR = 3.4; 95% CI = 1.6, 7.1); received money for sex (OR = 3.0; 95% CI = 1.2, 7.8); and 20 or more regular partners (OR = 2.5; 95% CI = 1.1, 6.1). CONCLUSIONS In Montreal, men who have sex with men are at risk for HBV infection, but a substantial proportion remain unvaccinated; new strategies are required to improve coverage. Men who have sex with men and who have a sexually transmitted infection, especially a genito-ulcerative infection, appear to be at particularly high risk for HBV infection.

Risk factors associated with HIV infection among young gay and bisexual men in Canada

Objective: To assess risk factors associated with HIV prevalence and incidence among gay and bisexual men in two prospective Canadian cohorts. Methods: The Vanguard Project and the Omega Cohort are prospective cohort studies of gay and bisexual men ongoing in Vancouver and Montreal, respectively. For this analysis, baseline sociodemographic characteristics, sexual behavior, and substance use data from these two cohorts were combined. Assessment of risk factors for HIV seroprevalence and seroconversion were carried out using univariate and multivariate analysis. Results: This analysis was based on 1373 gay and bisexual men aged 16 to 30 years. Men who were HIV‐seropositive at baseline (n = 48) were more likely to report living in unstable housing, to have had less than a high school education, and to have been unemployed than those who were HIV‐negative (n = 1325). HIV‐positive men were also more likely to report having engaged in sexual risk behavior, including having had consensual sex at a younger age, having had at least 6 partners during the previous year, ever having been involved in the sex trade, and having engaged in unprotected receptive anal intercourse. With respect to substance use, HIV‐positive men were more likely to report the use of crack, cocaine, heroin, and marijuana and to use injection drugs. Similarly, men who seroconverted during the course of the studies (n = 26) were more likely to report having less than a high school education and having lived in unstable housing at baseline. Compared with HIV‐negative men, men who seroconverted were more likely to report ever having been involved in the sex trade and engaging in unprotected receptive anal intercourse. Reports of cocaine use and injection drug use were also significantly higher for men who seroconverted compared with HIV‐negative men. Conclusions: Our data indicate that HIV‐positive gay and bisexual men are more likely to be living in unstable conditions and to report more risky sexual and substance use behaviors than HIV‐negative men.

Illicit Use of Methadone Among IV Drug Users in Montreal

Few studies have been done on the prevalence of illicit methadone use. Five hundred fifty-nine IV drug users recruited in various ways in Montreal were interviewed concerning their drug use as part of a longitudinal study on HIV infection. Of this number, 133 had heroin as their drug of preference and 426 cocaine. Among the cocaine group, 202 also used heroin. The lifetime prevalence of any illicit methadone use was 59.4% in the heroin group, 26.7% in the cocaine/heroin group, and 3.6% in the cocaine-only group. The 6-month (preceding the interview) prevalence of any illicit use was 42.1%, 6.9%, and 1.3%, respectively, and the prevalence of at least weekly illicit use during that period was 6.3%, 2.0%, and 0%, respectively. The prevalence of illicit methadone use is significant in the population studied. Whether this level of use will be affected by more stringent control on methadone prescription and dispensation remains to be demonstrated.

Factors associated with hepatitis B vaccination among men having sexual relations with men in Montreal, Quebec, Canada. Omega Study Group.

OBJECTIVE To determine factors associated with hepatitis B virus (HBV) vaccination status among HIV-uninfected men who have affective and sexual relations with men (MASM) in Montreal, Quebec, Canada. METHODS The Omega Cohort is a study of the incidence and psychosocial determinants of HIV infection among MASM in Montreal. Participants complete a questionnaire and are HIV-tested every 6 months. At baseline, we also performed testing for HBV markers and collected data on HBV vaccination history. RESULTS Forty-six percent of 653 participants had received at least one dose of HBV vaccination, whereas 28% were completely vaccinated. Lack of vaccination was associated with injection drug use, having > or =20 regular lifetime partners, living outside Montreal, not having sex in bathhouses, and not having consulted a physician aware of the participants sexual orientation. Among vaccinated MASM, incomplete vaccination was associated with having <20 lifetime casual partners, trading sex for drugs, having given goods for sex, having had unprotected anal sex with regular partners, and having no history of a previous sexually transmitted disease. CONCLUSION A significant proportion of Montreals MASM, some of whom are at risk of contracting HBV through sexual and parenteral transmission, have not been vaccinated for HBV. Men who have affective and sexual relations with men should be educated about the risk of HBV transmission and the seriousness of the disease.

Determinants of Hiv Seroconversion Among Men Who Have Sex With Men Living in a Low Hiv Incidence Population in the Era of Highly Active Antiretroviral Therapies

Objective: To estimate human immunodeficiency virus (HIV) incidence and associated risk factors among men who have sex with men (MSM) participating in the Omega Cohort Study in Montreal, 1996–2003. Methods: Longitudinal study of 1587 MSM seronegative at baseline with ≥1 six-month follow-up visit. Multivariate Cox regression with time-dependent variables was used for data analysis. Results: HIV incidence was 0.62 per 100 person-years (95% confidence interval: 0.41–0.84). In multivariate analyses compared with subjects not reporting any anal sex with serodiscordant or casual partners, those reporting anal sex with such partners (all P values <0.05), whether consistently protected [hazard ratio (HR) = 3.4], or unprotected exclusively receptive (HR = 12.0), exclusively insertive (HR = 4.7), or both receptive and insertive (HR = 8.3), were at increased risk of seroconversion. Sexual behaviors with seroconcordant regular partners were not associated with seroconversion. Conclusion: These results observed in a cohort of MSM with low HIV incidence provide new insights regarding the debate about harm-reduction strategies to prevent sexual HIV transmission.

Regional Variation in Travel-related Illness acquired in Africa, March 1997-May 2011

To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism.